Bags for containment of particulate products

ABSTRACT

The invention relates to a method and an apparatus for transporting, testing, filling and sealing a bag which is comprised of a bag body that can be spread out to form a rectangular cross section, said bag body being made up of two wider first and two narrower second bag walls, a bag bottom sealing the bag body at the bottom, a bag opening bordering the bag body at the top, and an opened bag seal, whereby the bag seal itself comprises first sealing flaps which are connected to the first bag walls respectively and stick out horizontally from the bag opening outwards, and towards the first bag walls at right angles, second sealing flaps which are connected to the second bag walls respectively and which lie—especially when folded inwards onto the bag opening—horizontally so that the first sealing flaps and the second sealing flaps form a frame-shaped sealing collar lying on a horizontal plane, by which during transporting, testing, filling and sealing the outer areas of the first sealing flaps are held by means of propelling conveying means.

[0001] The invention relates to a method for transporting, checking,filling and sealing a bag which is comprised of a bag body that can bespread out to form a rectangular cross section, said bag body being madeup of two wider first and two narrower second bag walls, a bag bottomsealing the bag body at the bottom, a bag opening bordering the bag bodyat the top, and an opened bag seal, whereby the bag seal itselfcomprises first sealing flaps which are connected to the first bag wallsrespectively and stick out horizontally from the bag opening outwards,and towards the first bag walls at right angles, second sealing flapswhich are connected to the second bag walls respectively and whichlie—especially when folded inwards onto the bag opening—horizontally sothat the first sealing flaps and the second sealing flaps form aframe-shaped sealing collar lying on a horizontal level.

[0002] The bag is designed in particular to be filled with pulverizedfilling products. The process of filling pulverized filling productsinto bags and the subsequent sealing of the bag seals brings to lightseveral problems which will be covered in the following. In thisconnection, particularly for paper bags, hot melting glue is usuallyapplied to the sealing surfaces for the purpose of sealing, and gluedtogether or, in the case of bags made from thermoplastic foils, sealingsurfaces lying on top of each other are thermally welded together.

[0003] One problem is presented by the formation of dust which isdifficult to suppress during the filling process leading to the soilingof the plant and working place stress and even to the risk of dustexplosions. This formation of dust must therefore be kept as low aspossible.

[0004] In order to keep the formation at a bearable level valve bags arewidely used in which a valve sleeve is glued in one end of a crossbottom element. The disadvantage of such bags lies in the reducedfilling speed which is limited by the valve cross section in which afiller neck with a diameter of few centimeters is integrated. Inaddition the manufacturing and recycling is more costly due to the useof additional valve sleeves.

[0005] When open-mouthed bags are being used the filling speed can beincreased however the entire sealing surfaces are dust covered after thefilling process so that the sealing is not always effected faultlessly.

[0006] A second problem lies in the fact that the area of the bag sealis inevitably covered by a layer of dust. A dust covered surface impedesthe gluing process using hot melting glues as well as the welding of thesurfaces of thermoplastic foils.

[0007] A further problem arises in that bags filled with pulverizedfilling products which are sealed after the filling process for exampleby folding over, have micro openings at the folding corners which inturn are connected to the bag interior via channels out of which fillingproducts can spill and through which -insect pests can gain accessespecially in the case of food stuffs.

[0008] This being the basis it is the aim of the present invention toprovide a method for transporting, testing, filling and sealing a bagwhich can be conducted with a most extensive suppression of formation ofdust and allows a sealing of the bag which is not influenced by theformation of dust.

[0009] The solution for this lies in the properties of the independentprocedure and device claims. These are based on a bag which is comprisedof a bag body that can be spread out to form a rectangular crosssection, said bag body being made up of two wider first and two narrowersecond bag walls, a bag bottom sealing the bag body at the bottom, a bagopening bordering the bag body at the top, and an opened bag seal,whereby the bag seal itself comprises first sealing flaps which areconnected to the first bag walls respectively and stick out horizontallyfrom the bag opening outwards, and towards the first bag walls at rightangles, second sealing flaps which are connected to the second bag wallsrespectively and which lie—especially when folded inwards onto the bagopening—horizontally so that the first sealing flaps and the secondsealing flaps form a frame-shaped sealing collar lying on a horizontallevel. A preferred embodiment and method for manufacturing such a bag isdescribed in the patent application of Chronos Richardson GmbH lodged atthe same time. An essential feature of the aforementioned method is thefact that the first sealing flaps are held in place by propellingconveying means during transport, testing, filling and sealing of thebag so that the bag can be kept suspended freely by these. This appliesespecially to the filling of the bag. Inside the transport means whichis particularly comprised of conveyor belt pairs, guide profiles orguide beads can support the parts of the aforementioned sealing collarwhich are positioned horizontally.

[0010] A procedure and a device for testing a bag stands out because ofthe fact that the flattened bag body is kept in its flattened shapebetween large-surface air permeated angle brackets and that a pressurejoint is tightly put onto the essentially horizontally positionedsealing collar with a clearance to the bag opening whereby compressedair is supplied for test purposes via the bag openings. If an excessivepressure drop occurs at the pressure joint the first sealing flaps willbe released by the transport means and the faulty bag is ejected.

[0011] A new method and a special apparatus for filling operations arecharacterized by a filler neck which has sealing compounds running alongthe edge of the bag opening enclosing the opening which are placed onthe sealing collar being positioned essentially horizontally before thefilling products are transferred into the bag. Therefore the sealingcollar is kept free of filling products and especially dust for thepurpose of a later sealing process. A special procedure and acorresponding apparatus for sealing the filled bag in the first step ischaracterized in that a cover sheet which is to be glued onto the areapreviously kept dust free by the filler neck, or welded to the sealingcollar, is placed on the essentially horizontal sealing collar. In thisconnection it is also essential that the sealing collar lies on a plainsurface whereby a cover sheet having been placed for example in such away that it can be unrolled, or in a level configuration, is “sealed”circumferentially with the dust free area.

[0012] The final folding of the bag seal can be effected in furthersteps using further sealing devices.

[0013] In the following details of the devices and the method accordingto the invention are described in more detail using the description ofembodiments.

[0014] Preferred embodiments of the apparatus according to the inventionby which the method according to the invention for transporting,testing, filling and sealing a special bag is discussed in detail, areshown in the following drawings.

[0015]FIG. 1 shows two stations of the apparatus according to theinvention in a perspective view

[0016] a) a station for guiding a bag into the apparatus,

[0017] b) a station for testing a bag in the apparatus.

[0018]FIG. 2 shows several stations of the apparatus according to theinvention in a perspective view

[0019] a) a station for testing a bag in the apparatus (partial view),

[0020] b) a station for filling a bag using a filler neck shown next toit,

[0021] c) a station for placing a cover sheet onto a filled bag (partialview)

[0022]FIG. 3 shows parts of the station for testing

[0023] a) as a cross section through the apparatus,

[0024] b) as a longitudinal section through the apparatus.

[0025]FIG. 4 shows parts of the station for filling according to FIG. 2bin a perspective view

[0026] a) with movable means of support of the filler neck in a upwardsretracted position,

[0027] b) with movable means of support of the filler neck in a downwardposition having been brought forward which is turned in under thesealing collar.

[0028]FIG. 5 shows parts of the station for filling according to FIG. 2b

[0029] a) as a cross section through the apparatus in the positionaccording to FIG. 3b,

[0030] b) as a longitudinal section with details according to FIG. 3aand 3 b.

[0031]FIG. 6 shows further parts of the filling station according toFIG. 2b

[0032] a) with deflectors in the position prior to the filling of thebag,

[0033] b) with deflectors in the position after the start of the fillingprocess of the bag.

[0034]FIG. 7 shows parts of a first sealing station

[0035] a) with a holding frame for separating a cover sheet,

[0036] b) with a double jet for gluing of a cover sheet,

[0037] c) with a prepared sealing collar of a bag,

[0038] d) with the cover sheet having been placed on the sealing collar,

[0039] e) with means of support for double-layered sealing rails.

[0040] In FIG. 1a) a feeder station of an apparatus according to theinvention is shown in which a bag 11 is held in a first configuration.This bag comprises a flattened bag body 10 whose lower part, inparticular its closed bottom part is not illustrated. The bag body 10forms a slot-shaped opening 12 at the top and on both sides towards theopening 12 are visible strips 13, 13′ which are still part of the bagbody. These strips 13, 13′ protrude at a right angles from the flattenedbag body 10 to both sides. They are limited by a binding edge 18 whichlies on a plane forming a rectangle separating the parts of the bag body10 from the parts of the bag seal 8. This is formed by first sealingflaps 21, 21′ which are situated outside the binding edge 18 andprotrude at a right angles away from the plane of the strips 13,13′, aswell as by second sealing flaps 22, 22′ which are situated inside thebinding edge 18 and are folded onto the plane of the strips 13, 13′.Outside the binding edge 18 final gussets 14, 14′ which also representpart of the bag body, follow the second seal gussets 22, 22′. The partsof the bag seal 8, i.e. the first and second sealing flaps, togetherform double-layered sealing rails 7, 7′, 7″, 7′″ which are limited onthe outside by a crease border 25 at the crossover of the first sealgussets 21 to the second seal gussets 22. At each of the four cornersthere are sealing gussets 7 and crease borders 25. The parts of thefeeder station 31 to be described in the following are just like theparts of the following stations also essentially symmetrical to theplane area defined by the flattened bag body 10 and are manufactured indouble, in particular, with the exception of some functional parts lyingabove the bag opening. The feeder station 31 comprises a pair of guideprofiles 32, 32′ which support the strips 13, 13′ of the bag body bymeans of upper surface sections. Below the profiles which jointly guidethe bag body 10, a pair of conveyor belts 33, 33′ is shown eachconsisting of pairs of deflection rollers which are not individuallydesignated and continuous loops which for the deflection rollersvertical axes of rotation affect the bag body below the guide profiles32 and enable the feeder process of a bag into the feeder station andthe forward feed of a bag out of the feeder station to the followingstation. In the testing station 41 following the feeder station, a bag11 with essentially matching configuration to the one in the feederstation is shown however the first sealing flaps 21 are each foldedtowards the outside into the plane area of the strips 13. Thus ahorizontally positioned circumferential sealing collar 16 is createdwhich is formed by the first sealing flaps 21, 21′, the second sealingflaps 22, 22′ and the seal gussets 7, 7′, 7″, 7′″. The sealing collar 16encloses the bag opening 15′ which is still closed by the strips 13,13′. Within this sealing collar both strips 13, 13′ are still lying onboth sides of the slot-shaped opening 12, as well as the final gussets14, 14′ outside the sealing collar 16. The station comprises anglebrackets 42, 42′ made from perforated plates and grills which are inturn positioned in pairs symmetrically such that their horizontal shankssupport the strips 13 and the vertical shanks enclose the flattened bagbody 10 between each other. The vertical shanks also here are notdisplayed in their complete form like the bag body. They are howeverdeveloped downwards to the extent that they support the entire bag body.The transfer of the first sealing flaps 21 from the vertical into thehorizontal position can be effected by the stationarily installeddeflection shoes which are located between the two stations. The testingstation 41 comprises furthermore pairs of conveyor belts on both sidesof the angle brackets of which only lower conveyor belts 43, 43′respectively are shown which are located directly below the firstsealing flaps 21, whereby the not denoted deflection rollers arearranged on a horizontal axis. In addition to the conveyor belts shown,complementary pairs of conveyor belts situated above have to be assumedwhich are each placed immediately above the first sealing flaps 21 sothat the pairs of conveyor belts can affect the first sealing flaps 21,21′ in pairs on both sides of the support profiles in such a way that abag is fed into and then moved out of the testing station. As anadditional element which is not shown here the testing station comprisesa pressure joint which has essentially the shape of a cuboid-shaped boxopen at the bottom, and to which compressed air can be supplied from therear side. The lower open, rectangular area is equipped with a sealingedge which can be placed along the following filling station 51according to the line of contact situated inside the sealing collar 16,for a filler neck. Once the compressed air supply has ceased the bag isheld essentially in shape by the angle brackets 42. Leakages in the bagbody would be recognizable by a pressure drop in the pressure joint. Insuch a case the marginally more movable pressure joint would be raised,and the angle brackets 42 and conveyor belts 43 symmetrical to the bagwould be separated from each other horizontally, and the respectiveupper and lower conveyor belts of the pairs of conveyor belts would beseparated from each other on both sides in perpendicular direction sothat as a result the bag would be discharged downwards from the testingstation under the influence of its own weight. A pair of the dischargerollers affecting the bag of which only one discharge roller 44 isvisible, can support this action as an additional safety measure. Afterthe completion of the testing process faultless bags are thentransported further towards the indicated filling station 51 by means ofthe conveyor belts.

[0041] In FIG. 2a) a testing station 41′ is shown in a modifiedembodiment in comparison to FIG. 1. The angle brackets 42 featuretransfer sections at their rear ends seen in conveyor direction whichseparate from each other in a y-shaped manner. The angle brackets arecompleted by grills which are only indicated under the strips 13 of thebag and on both sides of the bag body. The conveyor belts 43, 43′ aresituated on both sides of the angle brackets 42 and are provided indouble in pairs whereby the axes of their deflection rollers arepositioned horizontally. In this respect the arrangement andfunctionality corresponds to the conveyor belts described in connectionwith the testing station 41 in FIG. 1. However, only the respectivelower conveyor belts of the pairs of conveyor belts are shown. The baghas the same configuration as in the testing station according to FIG. 1therefore the description there is referred to. Details are not denotedhere. Above the sealing collar 16 which shows a drawn contact andsealing line a pressure joint 46 shown in an elevated position, with acompressed-air piping. From the position of the sealing line 45 it canbe seen that the seals provided at the pressure joint are supported frombelow, and the pressure joint surrounds the bag opening 15 for thepressure test with a clearance. Subsequent to the testing station 41′ afilling station 51 is shown in conveyor direction in FIG. 2b; thisstation features guide profiles 52, 52′ being separated by a certainclearance which are located immediately inside the conveyor belt pairs53, 53′ and which have the same clearance from each other as theconveyor belts 43, 43′ of the testing station 41. The conveyor belts aretherefore again affecting the first sealing flaps. The guide profiles 52which are located on the inside of these only support the inner sectionsof the first sealing flaps. Inside the sealing collar 16 of the bagpositioned inside the station a contact line 54 is drawn which matchesthe circumferential line of a filler neck 61 belonging to fillingstation 51. This filler neck is shown as being away from the sealingcollar overly far in a vertical direction while in actual fact only amarginal lifting motion of the filler neck 61 is possible. In theposition designed for the filling process the lower joint edge 62 isalso placed onto the contact line 54 while the filler neck 61 is liftedby a small margin from the sealing collar for transport purposes so thata filled bag can be transferred to the following first sealing station71 and a further bag can be fed from the testing station 41′. The fillerneck 61 is only shown in principal and comprises a feeding hopper 62 andan essentially cuboid-shaped nozzle 63 being open above and belowwhereby flap mechanisms can be positioned between the two partsmentioned. By releasing a filling quantity into the filler neck or fromthe filler neck/s the slot-shaped opening 12 is opened completely and atthe same time first side walls 1 and second side walls 2 are beingshaped at the bag 11 whereby the bag body 10 takes on a rectangularcross section shape and the bag is fully spread out. On the conveyorbelts 53 upper conveyor belts 53 o are partially shown apart from lowerconveyor belts 53 u so that it becomes clear here how bag is guided andheld between the pairs of conveyor belts. The retention forces of thepairs of conveyor belts are preferable designed in such a way thatduring and after the filling process the bag can be held suspendedfreely in the filling station 51, i.e. the bag bottom does not need tobe supported. This offers the advantage that bags of different lengthscan be filled in the same filling station. Within the contact edge 64which places itself onto the contact line 54 of the sealing collar, thenozzle 63 features a sealing edge being separated from it by a certainclearance, which is placed on a sealing line immediately at the openingedge of the bag opening 15. Thereby it is ensured that the area of thesealing collar 16 between the bag opening 15 and the contact line 54 iskept free from filling products during the filling process, i.e.particularly free from the formation of dust.

[0042] Following the filling station 51 a first sealing station 71 isshown in conveyor direction which features guide beads 72, 72′ and pairsof conveyor belts 73, 73′ in the same configuration as in the fillingstation 51. On the conveyor belts 73 upper conveyor belts 73 o partiallyworking together with lower conveyor belts 73 u are also shown here. Acover sheet 19 is placed onto the bag opening, on which a sealing edge20 is marked which essentially comprises the area previously kept freefrom dust, between the sealing edge on the bag opening and the contactline 54. After the first sealing station 71 a second sealing station canfollow whereby deflection shoes can be provided between the sealingstations which can transfer the sealing flaps into the position shown inFIG. 1a) and can even fold these on top of each other subsequent to agluing process, if necessary.

[0043] In FIG. 3a) a cross section through the testing station is shownwhile the bag is still flattened as is the case for testing. The pairsof angle brackets 42, 42′ and the pairs of conveyor belts 43 o, 43 u,43′o, 43′u are visible as components of the testing station alreadymentioned previously. The angle brackets support with their upper shanksthe inner parts of the first sealing flaps and the strips 13 of the bagbody. The vertical shanks of the angle brackets hold the bag body closetogether. From the pressure joint 46 first longitudinal seals 48 beingpositioned along the contact and sealing line are visible whichtherefore lie in the approximate center on the sealing flaps 21, 21′which continue until between the conveyor belts.

[0044] In FIG. 3b an longitudinal section through a bag in the testingstation is shown whereby the second sealing flaps 22, 22′ pointinginwards are cut. At the pressure joint 46 longitudinal seals 49, 49′ arevisible which are located immediately inside the contact and sealingedge of the pressure joint.

[0045] In FIG. 4 both support elements 65, 65′ belonging to a fillerneck 61 together with the respectively associated lifting and pivot pins66, 66′ are shown with respect to the bag opening 15 of a bag shownbroken off and which is inside the station in different positions. InFIG. 4a) the cut through support element 65 of half-washer shape issituated above the sealing collar 16 and above the bag opening 15. InFIG. 4b) the support element 65 is lowered in such a way that the cutthrough support element 65 of half-washer is positioned lower than thelevel of the sealing collar 8, i.e. with its upper side in the planearea spread out by the guide profiles 52, 52′. By turning the supportelement 65 by 180° after lowering it, it is shifted under one of thesecond sealing flaps 22. Although the bag is shown here in its alreadycompletely opened position the positioning of the support elements bylowering and turning by 180° has already been effected in theconfiguration, shown for example in FIG. 2a) of the bag, in which thebag is transferred to the filling station 51. The strips 13, 13′ arethereby only being pushed slightly downwards without incidentallychanging the shape of the bag essentially. Onto the cross web 67 in theposition shown in FIG. 3b) a seal edge is lowered from above to come incontact with the second sealing flaps 22 situated in between. Theembodiment in half-washer shape allows it to be screwed in from theposition according to FIG. 3a) to the support position according to FIG.3b). However, for the appropriate blade-shaped embodiment the loweringand horizontal shifting motion of a support element is also possible.

[0046] In FIG. 5a) a cross section through the filling station is shownfor a bag 11 already completely spread out as it is shaped during thefilling process. The pairs of guide profiles 52, 52′ and the pairs ofconveyor belts 53 o, 53 u, 53′o, 53′u are visible as components of thefilling station already mentioned previously. The guide profiles 52support with their upper shanks the inner parts of the first sealingflaps 21, 21′. The conveyor belts 53 press and hold the outer areas ofthe first sealing flaps 21, 21′. From the filler neck 61 the essentiallyparallel sided nozzle 63 with its contact edge is visible. In cut-awayareas, longitudinal seals 68 which position themselves on the areas ofthe sealing flaps 21, 21′ being supported by the guide profiles 52, areshown located immediately next to the edge of the bag opening 15. Theparts of the first sealing flaps are therefore sealed against admissionof filling products during the filling process. The nozzle 63 isdouble-walled as shown so that the free inner cross section of thenozzle 63 corresponds to the cross section of the bag opening.Furthermore the support element 65 with the trunnion 66 is shown in theposition lowered underneath the second sealing flap as known from FIG.4a) whereby the surface lies on the same level as the surface of theguide profile 52.

[0047] In FIG. 5b) a longitudinal section through a bag is shown in thefilling position whereby the double-walled nozzle 63 as well as the bag11 with the inwardly pointing second sealing flaps 22, 22′ can be seen.On the double-walled nozzle 63 transverse seals 69, 69′ are visiblewhich run immediately outside and essentially parallel to the edge ofthe bag opening 15. In the left half of the drawing the support element65 is shown in the position known and described in FIG. 4b) in which itsupports the sealing flap 22 from below against the nozzle 63 pressed onfrom above. In the right half of the drawing, the support element 65′ isshown in the position known and described in FIG. 4a) in which it isguided out of the bag area due to a rotating action of 180° and liftingof the trunnion 66. By lifting the nozzle 63 marginally the bag can betransported further. The area of the sealing flaps 22 lying outside theseals 69, 69′ is again being kept free from filling products, i.e. inparticular is dustfree. The transverse seals 69 connect to thelongitudinal seals 68 such that a circumferential sealing line iscreated.

[0048] In FIG. 6 further details from the area of a filling station 51are shown whereby for orientation purposes only the guide profiles 52,52′ are shown not however the pairs of conveyor lying sideways outsidethe guide profiles. In FIG. 6a) a bag is shown in a configuration as itis fed into the filling station, i.e. in particular with bag walls 1, 1′lying closely together, so that the body is flattened. The first sealingflaps 21, 21′ are supported from below by the guide profiles 52, 52′.The areas of the sealing flaps 21, 21′ protruding beyond are retained bythe conveyor belts not shown here. Beneath the visible second sealingflaps 22 a support element 65″ is shown whose underside is preferablyslightly conically truncated. The strips 13, 13′ of the bag body whichare essentially still located on the level of the sealing collar arethereby slightly pushed in whereby they are supported from below bydeflectors 81 being arranged in pairs. The deflectors 81, 81′ feature arotatable bearing arrangement around trunnions 82, 82′ with horizontalrotational axes running in the direction of the guide profiles 51. Themovement of the deflectors is dampened by the damper 83, 83′ which actupon the free ends of the deflectors by means of their piston rod 84,84′ via pivot pins 85, 85′, and which feature a swiveling bearingarrangement using pivot pins 86, 86′. If the entire filling quantity isreleased into the feeding hopper in the position shown in FIG. 5a) andfalls onto the wall sections 13, 13′ no tearing or destructive actioncan occur due to the support shown by means of the deflectors becausethe impact of the filling quantity is first of all captured by thedeflectors 81, 81′ softly giving way so that the filling product canonly increasingly spread out the bag in a controlled fashion from top tobottom until the position shown in FIG. 5b is reached. For this thedeflectors are perpendicular and lie parallel to the first bag walls 1,1′. The filled bag can be transported further from this position towardsa sealing station. A further bag which is still flattened can then befed in. Afterwards the deflectors must again be returned to theiroriginal position by means of the damping elements 83, as well as thesupport elements 65 previously pulled back which must again be guidedinto the bag opening and positioned underneath the second sealing flaps.

[0049] In FIG. 7 a sheet stack 94 of cover sheets is shown in a) ofwhich a first cover sheet 19 is indicated in a lifted off position.Above the sheet stack 94 a holding frame 95 is shown which can lift offa cover sheet and shift it sideways into a position in which a glueapplication can be carried out onto the cover sheet.

[0050] In b) a station with a double jet 96 and a single cover sheetwhich has glue on its underside is shown. The holding frame 95 can holdthe cover sheet 19 in the position shown. The double jet 96 can beguided in a rectangle along the edges of the cover sheet if itslongitudinal axis is kept parallel to it, thereby creating first gluebeads 97 along the longitudinal edges and double-layered glue beads 98,99 along the traverse edges.

[0051] In c) a sealing collar 16 with first sealing flaps 21 and secondsealing flaps 22 is shown which respectively form dual fold sealingcorners 7 at the corners. The sealing collar 16 encloses the bag opening15 of the filled bag. With a slight clearance to the edge of the bagopening 15 the sealing line 55 is drawn in, outside which the sealingcollar is kept dustfree during the bag filling process. Already duringthe manufacturing process of the bag sealing rails folded in double atthe cut are placed on the second sealing flaps 22 whose crease edge runsalong the inside of the bag opening 15, and which open to the outside ina V shape. A lower strip of these sealing rails 26 is glued or welded tothe corresponding second sealing flaps 22, an upper strip is placedagainst the crease edge and can be swung out opposite the lower strip.It can be seen that the essential part of these sealing rails 26 liesoutside the sealing line 55 and is therefore kept dustfree during thebag filling process.

[0052] In d) it can be seen that the cover sheet 19 is placed onto thebag opening 15. The first glue beads 97 are essentially glued to thefirst sealing flaps 21. The second glue beads 98 are glued to the upperstrips of the sealing rails 26. Outside the sealing rails 26 the secondglue beads 98 are immediately connected to the second sealing flaps 22.

[0053] In e) a vertical cross section through a bag is shown for whichthe cross section is carried out in lengthwise direction of the bagopening and the second sealing flaps 22 are folded inwards onto the bagbody. Near the bag opening the twofold sealing rails 26 are indicated.First spline tools 91 can drive under the swung open upper strips of thesealing rails 26, as shown in the left drawing, whereas upper splinetools 92 which are especially shaped at the lower holding frame 95, canpress the cover sheet 19 which is put on against them for gluingtogether the first glue bead 98. In order to press the second glue bead99 to the second sealing flaps 22 the first spline tool 91 must pulledback.

[0054] Variations of the material described herein are possible for theexpert without leaving the scope of the invention.

List of Reference Characters

[0055]  1 first bag wall  2 second bag wall  7 sealing gusset  8 bagseal  9 bag bottom 10 bag body 11 bag (finished) 12 opening(slot-shaped) 13 strips 14 final gusset 15 bag opening (rectangular) 16sealing collar 17 sealing line 18 binding edge 19 cover sheet 20 glueedge 21 first sealing flap 22 second sealing flap 23 inner area 24 outerarea 25 crease edge 26 sealing rail 31 feeder station 32 guide profile33 conveyor belts 34 transfer section 41 testing station 42 supportingprofile 43 conveyor belts 44 discharge roller 45 contact and sealingline 46 pressure joint 47 compressed air supply 48 longitudinal seal 49transverse seal 51 filling station 52 guide profile 53 conveyor belts 54contact line 55 sealing line 61 filler neck 62 feeding hopper 63 nozzle64 contact edge 65 support element 66 trunnion 67 cross web 68longitudinal seal 69 transverse seal 71 sealing station 72 guide profile73 conveyor belts 81 deflectors 82 pivot pin 83 damper 84 piston rod 85pivot pin 86 pivot pin 91 spline tool 92 spline tool 93 — 94 sheet stack95 holding frame 96 double jet 97 glue bead 98 glue bead 99 glue bead

1. A method for transporting, testing, filling and sealing a bag (11)which is comprised of a bag body (10) which can be spread out to form arectangular cross section, said bag body being made up of two widerfirst and two narrower second bag walls (1, 2), a bag bottom (9) sealingthe bag body (10) at the bottom, a bag opening (15) bordering the bagbody (10) at the top, and an opened bag seal (8), whereby the bag sealitself comprises first sealing flaps (21) which are connected to thefirst bag walls respectively and stick out horizontally from the bagopening (15) outwards, and towards the first bag walls (1) at rightangles, second sealing flaps (22) which are connected to the second bagwalls (2) respectively and which lie horizontally so that the firstsealing flaps (21) and the second sealing flaps (22) form a frame-shapedsealing collar (16) lying on a horizontal plane area for which theexternal areas (23) of the first sealing flaps (21) are held bypropelling conveying means (33, 43, 53) during transport, testing,filling and sealing.
 2. A method according to claim 1, characterized inthat at the start of the transport, the bag uppermost strips (13) of thefirst bag walls (1) are incorporated in the horizontal level of thefirst sealing flaps (21) and form a slot-shaped opening (12) when thebag body is flattened and shortened.
 3. A method according to claim 2,characterized in that at the start of the transport the uppermost strips(13) of the first bag walls (1) and the internal areas (24) of the firstsealing flaps (21) are immediately supported from below at the first bagwalls (1) by stationary guide beads (32).
 4. A method according to claim3, characterized in that that a bag (11) with a flattened bag body (10)is guided between perpendicular parallel support plates (42).
 5. Amethod according to claim 4, characterized in that that for the firstbag walls (1) being supported sideways by the support plates (42)compressed air is supplied through the bag opening (15) for the purposeof testing the seal of a bag (11).
 6. A method according to claim 5,characterized in that that due to negative testing of the seal of a bag(11) the support plates (42) and conveying means (43) are separated fromeach other in such a way that the bag (11) is discharged.
 7. A methodaccording to claim 1, characterized in that that for the filling of abag (11) a filler neck (61) sealing circumferentially is placed onto thearea of the sealing collar (16) from above whereby the first sealingflaps (21) and the second sealing flaps (22) are supported from below.8. A method according to claim 7, characterized in that that during thefilling of a bag (11) the first sealing flaps (21) are supported byguide beads (52).
 9. A method according to claim 7, characterized inthat that during the filling of a bag (11) the second sealing flaps (21)are supported from below by the support elements (65) having beenpositioned between the second sealing flaps (22) and the uppermoststrips (13).
 10. A method according to claim 7, characterized in thatthat the filling of a bag (11) is effected while the essentiallyflattened bag body (10) still features a slot-shaped opening (12), andthe uppermost strips (13) of the first bag walls (1) included in theplane of the sealing collar (16) are thus supported from below.
 11. Amethod according to claim 7, characterized in that that for the fillingof a bag (11) it is exclusively held fast by the outer strips of thefirst sealing flaps (21) and the bag body (11) is hanging suspendedfreely during the filling process.
 12. A method according to claim 7,characterized in that that sealing rails on the second sealing flaps(22) are folded outwards from the bag opening (15) before the fillerneck (61) is placed on the sealing collar (16).
 13. A method accordingto claim 1, characterized in that that for sealing a bag, a cover sheet(19) is placed onto the sealing collar (16) and is connected with it inan area which is located outside the area sealed by the filler neck(61).
 14. A method according to claim 13, characterized in that thatafter placing the cover sheet (19) onto the sealing collar (16) thefirst sealing flaps (21) are folded inwards and connected with eachother.
 15. An apparatus for transporting, testing, filling and sealing abag (11) which is comprised of a bag body (10) which can be spread outto form a rectangular cross section, said bag body being made up of twowider first and two narrower second bag walls (1, 2), a bag bottom (9)sealing the bag body (10) at the bottom, a bag opening (15) borderingthe bag body (10) at the top, and an opened bag seal (8), whereby thebag seal itself comprises first sealing flaps (21) which are connectedto the first bag walls respectively and stick out horizontally from thebag opening (15) outwards, and towards the first bag walls (1) at rightangles, second sealing flaps (22) which are connected to the second bagwalls (2) respectively and which—especially when folded inwards onto thebag opening—lie horizontally so that the first sealing flaps (21) andthe second sealing flaps (22) form a frame-shaped sealing collar (16)lying on a horizontal plane whereby the apparatus features stationarilyarranged propelling conveying means in the shape of arrangements,running parallel to each other, of pairs of upper and lower conveyorbelts respectively (33, 43, 53) or conveyor rollers between which outerareas (23) of the first sealing flaps (21) are held from above andbelow.
 16. An apparatus according to claim 15, characterized by a feederstation (31) with guide beads (32) which are positioned closely to thebag walls (1, 2) supporting the sealing flaps (21) of a bag passingthrough.
 17. An apparatus according to claim 15, characterized by atesting station (41) with parallel support plates (42) supporting theessentially flattened bag body (10) of a fed bag (11), especially in theshape of grills as well as a test plate for compressed air which isequipped with circumferential sealing compounds which are to be placedon the area of the sealing collar (16) of a fed bag (11).
 18. Anapparatus according to claim 15, characterized by a filling station (51)with a vertically movable filler neck (61) which is equipped withcircumferential sealing compounds (68, 69) which are to be placed on thearea of the sealing collar (16) of a fed bag (11).
 19. An apparatusaccording to claim 18, characterized by support elements which supportthe first sealing flaps (21) and the second sealing flaps (22) of a fedbag below the sealing compounds (68, 69) of the filler neck (61).
 20. Anapparatus according to claim 18, characterized by parallel guide beads(52) which are located inside the conveying means (53) in order tosupport the first sealing flaps (21).
 21. An apparatus according toclaim 18, characterized by support plates (65) which are located insidethe filler neck (61) being height adjustable, rotatable, pivoting ortraversely movable, and which can be inserted from above the sackopening (15) of a fed bag (11) to below the level of the sealing collarand moved underneath the second sealing flaps (22) supporting these. 22.An apparatus according to claim 15, characterized by a pair ofdeflectors (81) which are rotatable in a damped and flexible way aroundparallel hinges (82) which run in the direction of the second sealingflaps (22), from an approximately horizontal position being backsweptdown and inwards, and which support, in their approximately horizontalposition, from below the strips (13), being included in the level of thesealing collar (16), of the first walls (1) and release the full bagcross section when they are pivoted downwards.
 23. An apparatusaccording to claim 15, characterized by a first sealing station (71)equipped with gluing means for gluing a single cover sheet (19) and withdepositing means for depositing a cover sheet (19) onto the sealingcollar (16) of a bag (11) inside the sealing station.
 24. An apparatusaccording to claim 23, characterized by a first sealing station with atleast one pad-roller which is located above the sealing collar (16) andwith counterpressure rollers which are located under the sealing collarbelow at least the one pad-roller and which together push the firstsealing flaps (21) and a cover sheet (19) together while rolling againsteach other.
 25. An apparatus according to claim 23, characterized by afirst sealing station with support wedges (91) which are moved underoutwardly folded sealing rails (26) particularly of the second sealingflaps (22) and are adapted by means of pad wedges (92) which complementthe support wedges (91), and can be lowered—to press a cover sheet (19)onto the outwardly folded sealing rails (26)—to the outer edges of thecover sheet (19).
 26. An apparatus according to claim 15, characterizedby a second sealing station in which the sealing flaps (21, 22) are bentup from the level of the sealing collar (16) and are connected to eachother.
 27. A bag for the purpose of being filled with bulk material,said bag being comprised of a bag body (10) which can be spread out toform a rectangular cross section, said bag body being made up of twowider first and two narrower second bag walls (1 or 2), a bag bottom (9)sealing the bag body (10) at the bottom and a bag opening (15) borderingthe bag body (10) at the top, denoted by first sealing flaps (21, 21′)which stick out from the bag opening (15) outwards and towards the firstbag walls (1) at right angles, and second sealing flaps (22, 22′) whichare connected to the second bag walls (2) respectively and are foldedinwards onto the bag opening so that the first and the second sealingflaps (21, 21′; 22, 22′) form a frame-shaped sealing collar.